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April 2003 $4.95 SOLVING THE NEUTRINO MYSTERY • RECOGNIZING ANCIENT LIFE APRIL 2003 $4.95 WWW.SCIAM.COM James D.Watson discusses DNA, the brain, designer babies and more as he reflects on Grid Computing’s Unbounded Potential Ginkgo Biloba Will Mount Etna and Memory Explode Tomorrow? Delivering Drugs with Implanted Chips COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. april 2003 contentsSCIENTIFIC AMERICAN Volume 288 Number 4 features ASTROPHYSICS 40 Solving the Solar Neutrino Problem BY ARTHUR B. MCDONALD, JOSHUA R. KLEIN AND DAVID L. WARK After 30 years, physicists fathom the mystery of the missing neutrinos: the phantom particles change en route from the sun. BIOTECHNOLOGY 50 Where a Pill Won’t Reach BY ROBERT LANGER Implanted microchips, embedded polymers and ultrasonic blasts of proteins will deliver next-generation medicines. 66 James D. Watson VOLCANOLOGY 58 Mount Etna’s Ferocious Future BY TOM PFEIFFER Europe’s most active volcano grows more dangerous, but slowly. CELEBRATING THE GENETIC JUBILEE 66 A Conversation with James D. Watson The co-discoverer of DNA’s double helix reflects on the molecular model that changed both science and society. LIFE SCIENCE 70 Questioning the Oldest Signs of Life BY SARAH SIMPSON Researchers are reevaluating how they identify traces left by life in ancient rocks on earth—and elsewhere in the solar system. INFORMATION TECHNOLOGY 78 The Grid: Computing without Bounds BY IAN FOSTER Powerful global networks of processors and storage may end the era of self-contained computing. MEDICINE 86 The Lowdown on Ginkgo Biloba BY PAUL E. GOLD, LARRY CAHILL AND GARY L. WENK This herbal supplement may slightly improve your memory—but so can eating a candy bar. Also: Mark A. McDaniel, Steven F. Maier and Gilles O. Einstein discuss other “brain boosters.” www.sciam.com SCIENTIFIC AMERICAN 7 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. departmentsSCIENTIFIC AMERICAN Volume 288 Number 4 10 SA Perspectives Get real about abstract worries. 12 How to Contact Us 12 On the Web 28 100 16 Letters 20 50, 100 & 150 Years Ago 22 News Scan 34 Innovations Metanomics develops a way to peek ■ Manned spaceflight after Columbia. into plant metabolism. ■ Spilled oil off Spain’s coast proves too slippery to predict. 37 Staking Claims ■ Bacteria thawed an ancient earth. The case for restricting patents that hinder basic ■ Suspicions about the speed of gravity. biomedical research. ■ Do gray wolves still need protection? 92 Working Knowledge ■ More proof that “clone” doesn’t mean “copy.” Patches that deliver drugs. ■ By the Numbers: Poverty in the U.S. ■ Data Points: Invasive species. 94 Technicalities Tablet PCs are high-tech tools for scribblers. 97 Reviews Faster Than the Speed of Light looks provocatively at the new cosmology. 94 columns 38 Skeptic BY MICHAEL SHERMER The Three Laws of Cloning. 100Puzzling Adventures BY DENNIS E. SHASHA Graphing the origins of species. 102 Anti Gravity BY STEVE MIRSKY Burgers and joints. 103Ask the Experts What is the importance of the new discovery? 104Fuzzy Logic BY ROZ CHAST Cover image by Mike Medicine Horse, Hybrid Medical Animation Scientific American (ISSN 0036-8733), published monthly by Scientific American, Inc., 415 Madison Avenue, New York, N.Y. 10017-1111. Copyright © 2003 by Scientific American, Inc. All rights reserved. No part of this issue may be reproduced by any mechanical, photographic or electronic process, or in the form of a phonographic recording, nor may it be stored in a retrieval system, transmitted or otherwise copied for public or private use without written permission of the publisher. Periodicals postage paid at New York, N.Y., and at additional mailing offices. Canada Post International Publications Mail (Canadian Distribution) Sales Agreement No. 242764. Canadian BN No. 127387652RT; QST No. Q1015332537. Subscription rates: one year $34.97, Canada $49 USD, International $55 USD. Postmaster: Send address changes to Scientific American, Box 3187, Harlan, Iowa 51537. Reprints available: write Reprint Department, Scientific American, Inc., 415 Madison Avenue, New York, N.Y. 10017-1111; (212) 451-8877; fax: (212) 355-0408 or send e-mail to [email protected] Subscription inquiries: U.S. and Canada (800) 333-1199; other (515) 247-7631. Printed in U.S.A. 8 SCIENTIFIC AMERICAN APRIL 2003 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. SA Perspectives Get Real When the cloning of a human was announced last The answer from technocynics is yes. In his book last December, political and spiritual leaders condemned year Fukuyama drew a line between medical therapy it as an affront to the “dignity of man.” That kind of (OK) and genetic enhancement (not OK) but went on rhetoric is popping up all over the place. Political sci- to advocate a ban on all cloning, even the therapeutic entist Francis Fukuyama warns that genetic engineer- kind. Similarly, Joy has called for a “relinquishment” ing and Prozac-like drugs augur “a ‘posthuman’ stage of all—all—research into robotics, nanotechnology of history.” Bill Joy, co-founder of Sun Microsystems, and genetic engineering. Where does this absolutist frets over robotics and nanotechnology: “On this path stand leave the rest of us? We have watched our par- our humanity may well be lost.” ents and grandparents waste away from cancer and Even the Economist, a magazine Alzheimer’s disease. We have seen children die of dia- not usually given to apocalyptic betes and friends fall to depression, malaria and HIV. predictions, worries that neuro- If it comes down to a choice between the vague unease science could “gut the concept of that emerging technologies conjure up or the very un- human nature.” vague suffering they could cure, we know how we Like their counterparts in would decide. earlier ages, these commentators The technocynics basically want us to grin and bear argue that technology is running it, lest our attempts at self-improvement do more harm ahead of our ability to deal with than good. Yet if history is any guide, fears about the ANXIETY over genetically it; although scientific progress is impact of new technologies generally wind up sound- modified food often reflects all well and good, we have to rein ing pretty silly. Thoreau regarded trains, telegraphs, abstract worries about science. it in. Such views are often called newspapers and even mail delivery as dehumanizing. neo-Luddism, but frankly, that Late Victorians predicted that industrialization and ur- does not do justice to the Luddites. Those machine- banization would cause our species to degenerate to a smashing textile workers were reacting to immediate prehuman state. In the 1970s critics of in vitro fertil- threats, such as losing their jobs. Today’s concerns ization said it would create monstrous or deranged ba- tend to be abstract, and that is their problem. bies. In all these cases, abstract worries gave way to A science magazine is all in favor of abstract think- mundane ones. New technologies did bring new prob- ing, but at some point abstraction needs to make con- lems, but people worked around them. Few would, in tact with reality. And the reality of research bears little retrospect, ditch the technologies altogether. resemblance to the technocynics’ horror stories. Will The biggest danger, then, is not that science will run cloning, for example, open the door to “designer ba- ahead of ethics, but the opposite: that ethical hair trig- bies”? Maybe one day. For now, though, researchers gers will paralyze worthy research. Striking a balance are struggling to develop cloning just to grow tissues that is not easy. Bioethicist Gregory Stock offers a sound a patient’s immune system won’t reject. Even would-be prescription: “We should deal with actual rather than Corbis Sygma baby cloners don’t purport to fiddle with the genome. imagined problems.” To stop research is to give up try- Are people supposed to give up the prospect of life- ing to make the world a better place. It denies human saving therapies to avoid a distant, hypothetical threat? nature in order to save it. SION TOUHIG THE EDITORS [email protected] 10 SCIENTIFIC AMERICAN APRIL 2003 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. How to Contact Us On the Web WWW.SCIENTIFICAMERICAN.COM EDITORIAL ADVERTISING For Letters to the Editors: www.sciam.com has electronic Letters to the Editors contact information for sales FEATURED THIS MONTH Scientific American representatives of Scientific American in all regions of the U.S. Visit www.sciam.com/ontheweb to find these 415 Madison Ave. and in other countries. 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